Solar cells and solar cell modules convert sunlight into electricity. These devices are traditionally mounted outdoors on rooftops or in wide-open spaces where they can maximize their exposure to sunlight. When sunlight intensity increases, electrical output from solar cells and solar cell modules also increases. Unfortunately, increasing sunlight intensity also typically means increased normal operating cell temperature (NOCT) of the solar cell. For solar cells and solar cell modules, excessive heat decreases the conversion efficiency of these devices. NOCT for most solar cell modules is around 47° C. Many solar cell modules lose about 0.5% efficiency for every degree of increase in NOCT. A variety of factors may contribute to increased NOCT such as greater ambient air temperature during the day, increased temperature of the solar module itself from extended sun exposure, or radiant heat from ground surfaces and other nearby surfaces which may emit heat generated from sun exposure.
A central challenge in finding suitable cooling techniques for solar cells and solar cell modules lies in finding solutions that are cost effective and easily integrated with the solar cell configuration. Although it is desirable to reduce NOCT, cumbersome or expensive cooling techniques present more cost than the conversion efficiency gained by keeping the solar cells cool. Traditional solar cell modules pose a particular challenge as the multi-layer pottants used in these modules are poor thermal conductors and do not provide an efficient thermal path for drawing thermal energy away from such solar cell modules. The challenge is even greater for modules with traditional thin-film solar cells which present heat transfer issues at the solar cell level, prior to reaching the solar module level. Traditional thin-film solar cells are typically formed on glass substrates. The thickness of glass substrates and the inherently low thermal conductivity of glass substrates complicate the cooling process as there is more mass to cool and the glass acts as a thermal barrier. Mounting thin-film glass substrate solar cells in traditional module packaging further complicates matters.
Due to the aforementioned issues, improved thermal management schemes are desired for solar cells, solar cell modules, and/or similar photovoltaic devices.